REPORT OF THE CHEMIST. 201 



whether rice brans, rice polishes, and similar by-products have been 

 adulterated with hulls. Studies have also been made upon the differ- 

 ence in composition of natural brown and of polished rice. The 

 pearling of barley and the use of barley as food have been investi- 

 gated. The studies upon the determination of grades of flour, upon 

 the effect of granulation upon the baking (juality of flour and upon 

 wheat substitutes in the baking of bread have been continued. It 

 has been found possible to make good flour and bread from einkorn, 

 emmer, spelt, and Polish wheat. 



Fruits and vegetables. — The changes in chemical composition that 

 take place in the ripening of California olives, oranges, grapefruit, 

 and cantaloupes, and of Florida oranges and grapefruit have been 

 investigated. Data upon the composition of sound and frozen lemons 

 have been published. Several varieties of California avocados have 

 been examined to assist growers in choosing the best varieties. Bulle- 

 tin 452, " The Composition of American Grapes Grown in the Central 

 and Eastern States," has been issued. Studies have been made to 

 correlate the properties of tomato products with the quality of the 

 raw material from which they are made with special reference to the 

 amount of decayed material used in the preparation of such products. 



Sirup .^ sugars. — Eevisions of Farmers' Bulletins 477, " Sorghum 

 Sirup Manufacture," and 516, " The Production of Maple Sirup and 

 Sugar," are about to be issued. A chapter on " Jelly and Jelly Mak- 

 ing " has been contributed to Farmers' Bulletin 853. 



The investigations upon the two new heptose sugars, d-manno- 

 ketoheptose from the avocado, and sedoheptose from Sedum spectahile 

 have been printed. A number of papers have been published upon the 

 relation between the rotatory power of sugars and sugar derivatives 

 and their chemical constitution. A number of new sugar derivatives 

 have been prepared and made the subject of publications. 



Flora of foodstwlfs. — The necessity of carefully examining floating 

 grounds for the self purification of polluted oysters during a con- 

 siderable period of time to guarantee against the existence of occa- 

 sional sources of serious pollution before the commercial utilization 

 of such grounds should be approved, has been demonstrated. Such 

 grounds are available for each of the oyster-producing areas of the 

 Atlantic seaboard and upon them oysters cleanse themselves more 

 rapidly than has been supposed. Unpolluted shucked oysters, taken 

 from muddy or dirty bottoms, may become polluted in the process 

 of washing unless certain precautions be taken. Satisfactory meth- 

 ods for washing have been determined and the washing apparatus 

 has been improved. Experiments upon the hibernation of oysters in- 

 dicate that the oysters pass into this condition at a temperature of 

 the water of somewhat above 45° F. Data on the bacteriology of the 

 shell liquor and meats of oysters have been published. 



In order to determine whether or not an injustice might be done to 

 a bottler of drinking water through the examination of his product a 

 long time after bottling, the changes that the flora undergoes on 

 storage of the water w^ere investigated. No such injustice can be done 

 since most organisms, including B. coli, fall off in number during 

 storage. A few species not regarded as associated with pollution may 

 multiply, especially in waters with a certain mineral content. The 

 presence of a considerable number of molds in bottled waters is 

 clearly indicative of storage. 



